The investigation of the corrosion of a lid made from a tin lead alloy of a 200 years old beer jug induced by the degradation of the potash based glass revealed SnO, Cerussite (PbCO3) and K(OH)center dot 2PbCO(3) as main corrosion product. A model experiment, simulating the corrosion of lead at room temperature confirmed the formation of K(OH)center dot 2PbCO(3) as a corrosion product in alkaline, potassium containing medium. For detailed characterization K(OH)center dot 2PbCO(3) was prepared by hydrothermal synthesis, as well. K(OH)center dot 2PbCO(3) crystallizes in space group P6(3)/mmc with lattice parameters of a = 5.3389(1) angstrom and c = 13.9295(5) angstrom. The structure consists of Pb-(OH)(1/2)(CO3)(6/9)[CO3](3/9)(1/2-) layers and intercalated K+ and exhibits a close relationship to the crystal structure of hydrocerussite (Pb(OH)(2)center dot 2PbCO(3)), also known as "lead white". A novel structure family, Mn+(OH)(n)center dot 2PbCO(3) (with n = 1,2), was identified by structure solution of K(OH)center dot 2PbCO(3), which can be assigned to a 2H-type subspecies and,detailed comparison to Pb(OH)2 center dot 2PbCO(3), which represents a 3R-type subspecies.